JERUSALEM  Threats of withdrawing foreign aid to the Palestinian Authority following the Hamas election victory jeopardize environmental projects vital to Israel as well, Palestinian, Israeli and international officials said in a meeting Tuesday.

The militant Islamic Hamas, considered a terrorist group by the EU and United States, won the Jan. 25 parliamentary election and is expected to lead the next Palestinian government. International donors have said they will withhold aid unless Hamas pledges to disarm and recognize Israel. Hamas officials have rejected the demands.

The experts, speaking at a meeting sponsored by Friends of the Earth Middle East, an environmental group, warned cutting aid to the Palestinians would have regional consequences.

International funding and cooperation between Israel and Palestinian municipalities have made several waste disposal projects possible in the West Bank during the last few years, despite violence, said U.S. diplomat William Taylor.

"How these projects will move forward is the question that we are trying to deal with right now," Taylor said. How the international donor community deals with the rise of Hamas "is clearly going to be an issue," in the region's environmental progress, he said.

Cutting off funding for projects in the West Bank will harm Israel and the region because "pollution knows no boundaries," said Ilan Nissim, head of the solid waste division of the Israel's Environment Ministry.

Experts focused on the waste-contaminated groundwater in the West Bank, shared by Israelis and Palestinians. The water is supposed to be purified by natural processes, but the seepage of solid waste pollutants into the ground has damaged the process, according to a report issued Tuesday by Friends of the Earth.

Over the last few years, about $10 million (euro8.3 million) from the World Bank has helped clean up many dumping areas and build a modern landfill near Jenin in the northern West Bank, said Ibrahim Dajani of the World Bank.

German and American money has also paid for landfills and garbage collection in other parts of the West Bank, officials from the U.S. Agency for International Development and the German Development Bank said.

"We need this money to solve this dangerous problem," said Rayeq Hamad, environmental engineer in the Tulkarem municipality in the northern West Bank.

If governments stop providing money to the Palestinians Authority, non-governmental organizations will need to step up efforts, said Barbara Belding, a USAID officer in Jerusalem.

But some doubted NGOs could make up for money provided by governments for environmental projects.

"The role of NGOs and government agencies are different. They supplement each other and can't replace each other," said Kazuhiko Sakamoto, of the Japan International Cooperation Agency

The fact that Israeli and Palestinian officials met to talk about common environmental problems less than a week after the Hamas victory was a good sign, said Gidon Bromberg, Israeli director of Friends of the Middle East.

"It is the future drinking water of both people," Bromberg said. "There are good opportunities to move forward despite the uncertainty."